On Mon, 1 Apr 2013 23:15:07 -0700 (PDT), Christian Kujau wrote: > Hi, > > my machine (PowerBook G4) just crashed and the only thing netconsole was > able to transmit was: > > ------------[ cut here ]------------ > kernel BUG at /usr/local/src/linux-git/fs/ext4/inode.c:1591! > > But (unfortunately) nothing more. I have no clear way to reproduce this, > but I have some kind of a (longish) backstory to this, see below. The > system is running 3.9-rc4, its .config and dmesg: > > http://nerdbynature.de/bits/3.9.0-rc1/config.gz (oldconfig'ed to -rc4) > http://nerdbynature.de/bits/3.9.0-rc1/dmesg.txt (w/o the calltrace at the end) > > > I was having trouble all day downloading a file via bittorrent to an > ext4 filesystem. It came always back as corrupted, though I won't be able > to point out the corruption, as don't know the contents of the source > file. The ext4 filesystem sits on top of a dm-crypt LUKS device: > > /dev/mapper/wdc0 on /mnt/data type ext4 (rw,nosuid,nodev,noexec,relatime,data=ordered) > > While looking around as to why the file would be corrupt, the internet > suggested "bad memory" or "bad disk" or "kernel bugs". I have dismissed > the first two, as the system is rock-stable otherwise and dmesg has no > kernel messages suggesting disk or filesystem problems. Unfortunately it is like a regression which we missed due to s390x and ppc is not well tested. > > The file in question is ~800 MB in size. Not getting any further on a > solution to my corrupted file, I decided to download a 4.3GB Fedora > installation image via bittorrent to the same filesystem and that's when > the machine crashed, leaving only the single BUG message as a hint. Ohh that is sad. Unfortunately I can't reproduce this on my own environment. I have power mac pro G5 but w/o graphics card, so i cant install linux on it. If you know how to do that w/o monitor please let me know. So you just do bunch of writes/mmap to fallocated area. The only guess I have is that some bug in extent status tree Please run test with a patch which was posted here: http://marc.info/?l=linux-kernel&m=136455173926544&w=2 This patch enable sanity checks for extent_status tree. Also please try following patch. It voluntary disable es_lookup functionality.